Describe the impact of motor vehicles and public transportation in urban areas below and provide examples of each.

Volcanic irruption is most likely to be violent when a) volcanoes near to the sea b) the neck of the volcano is sealed by a plug c) the lava is viscous d) the lava reaches the surface through a fissure e) the volcano is on the ocean floor

How are the arctic and antarctic circles alike?

What's the inner core of the jovial planets made of